Door expander



April 22, 1930. R s. HElsE DOOR EXPANDER original Filed sept. 29, 1928 2Sheets-Sheet 1 ,WEE

Aprill 22, 1930. R 5, HElSE Y 1,755,591

' DooR EXPANDER Original Filed Sept. 29, 1928 2 Sheets-Sheet 2ascoeezie;

Satented pr. 22x,` A.1793() UNlTEDfsTAT-Es PATENT.- oFFIcE i i p noscoEs. HEIsE, on: DAYTON, 01110 DOOR EXP-ANDER l Applieetien ineav september29, 1928, se'riei No. 309,276.v Renewed Merenda, 1930. "1'

f This invention relates to a doorexpander andcontractor and` is:particularly adapted Y for use inconnectionwith electricovens and thelike.

y This invention is fully described in the following specificationandshown in the accompanying drawings, in whichf v vFigure'lris apartialvertical longitudinal section through an` electric oven embodyingthe invention; j e

Fig. 2 is a partial section on line 2 of Fig. 1; Figp is a` partialenlarged detail of one of the cam followers; .f p. .y Fig. 4is a partialenlarged section similar .to Fig.r 1, showing ya modified form oftheinvention; and

Fig. 5 is a partial'view on line 5l of Fig. Y l, showing the interiorconstructionof the door.- l

-The embodimentfillustrated comprises an electricV oven having a housing10 preferably of sheet metalwithin which isV secured an oven Alining 11of sheet metal which is very Y and forcing the tapered periphery 19 ofthe largely heat-insulated from the housing 10. The lining 11 has anoutwardly tapered opening 12 into which snugly ts ak door A.

The tapered portion 12 terminates in a' t iange A13 which is backed bymeans of arcorrespondingly-shaped'sheet metal reinforcing member 14, thewhole being 4secured together by means of screws 15. Akmoisture-collecting ring 16 is also held by the screws 15'and closelysurrounds the periphery ofthe door A sotas to .form a pocket 17 at thebottom of the door unitwhich willv collect any mois'- ture which mayleak past the door, or which may run out'from the bottom of the oven.

LThe door A has a sheet metal lining 18, pref` erably of aluminum, which4has a tapered periphery 19. This door is'generally' rec-v tangular inform, the corners being rounded,

' metal, are -provided with cutaway'portions 20a. The die for stampingthis portion`20"L vmay be moved in andv out, thereby varying as shown inFig. 2. Y The door A is moved bodily 4forward-,into

place, by means of mechanism such as that shown in myy pendingapplication, Serial No. 121,145, filed July k8, 1926. This makes it*possible to use ataperejd door Such as that shown.` It is highlydesirable, however, that this door,l after being moved in place, be

tightly sealed, and this is afzcomplishedlbyy means of expander arms 20which are pref? uerably placed one at each of the four corners of thedoor, these being forced outwardly or inwardly by means of an operatingllever l21.v

' .Each of the expander'arms 20is provided'55 with a c am follower 22shown in detail. in Fig. 3, each of lwhich hasv aseriesY of spiral teeth23 whichengagel similarly shaped spiral teeth on the face of the cam 24which is secured to the operating lever 21 by means ofV 60 1.a screw 25.The cam `'24 has a central extension'26 which is screw-,threaded toreceive a nut 27. This nut, in turn, retains a washer 28 which looselyengages the back of the four cam followers 22, so that these `cam fol 65`lowers may simultaneously move in and out as the lever arm 21' isrocked forward or backward.

It willbe observedthat vas the operating lever 2lv is movedin aclockwisedirectio'n as 70 seen from the front of the oven, thel ycamfollowers 22 will be forced outwardly, thereby pressing the expander arm2O outwardly with-draw'the arms 2O onfmotion of the cam 24 in acounter-clockwise direction. At the 85 same time the arms 20-are'positively secured to the tapered periphery by` means of smallVdepressed plates 29 which are secured in place by means of screws 30.

AIt will also be observed that the expander 90 arms 2O, preferablystamped from sheet the width of the bifurcat'ed arms thus formed, 95

land also varying the stiffness of the expander arms 20. e i

`To prevent permanent deformation Yor stretching of the door mounting,duetto repeated usage of the expander, I have'pror-v 100 n feo videdmeans whereby the door may be expanded without stretching the sheetmetal lining at all. This consists of a series of vertical andhorizontal grooves 31 and 32 respectively across the door and providingmetal which can be flexed without stretching. These grooves extendaround the periphery of the door, as shown in Figs. 2 and 5 and thetapered opening 12 is accordingly grooved to fit the grooves in the doorso that hermetic sealing of the opening maybe accomplished. The canifollowers 22 may be guided by means of a series of clips 33 which areriveted or otherwise secured to a central plate 34.'

In'V F ig. 4 is a shown a modified-form of expander and contractor asapplied to a door A having a series of door expander arms 20h, to whichare riveted cam followers 22a which engage a cam 24 secured to anoperating lever 21a. This lever also carries a cam 24h, which has spiral'cam teeth engaging the outer portion of the follower 22a. In both casesmeans are provided for adjusting the angular position of the levers 2land 21a with respect tothe cams 24 and 24a respectively.

It will be observed that a very simple and effect-ive means is providedfor positively expanding and contracting the door within the 'dooropening. It will also be observed that the pressure of the expanders isexerted immediately beneath the reinforcing flange 14.

While I have shown and described but a l single embodiment of thisinvention, it is to be understood that it is capable lof manymodifications. Changes, therefore, in the construction and arrangementmayV be` made which do not depart from the spirit and scope of theinvention asdisclosed in the appended claims. v

f I claim:

, 1. In a structure of the class described, a

receptacle having an opening, a door adapted g to move into vsaidopening to. close'the same, said door having a sheet metal facing, meansin the doorfor expanding said sheet metal into contact-with said openingto tightly close the same, means for positively drawing said Sheet metalinwardly to release said door f from the opening, and a member foroperating both said means.

2. In a structure of the class described, a; Y y

, 1 wardly into contact with said lining, and

i receptacle having a sheet metal lining terminating in a tubularopening, ,a support for said opening, a. door adapted to move into saidopening to close the same, said door having a sh'eetmetal facing, meansin the door for expanding said sheet metal into contact'with lsaidopening to tightlyVv close the same, means for positively drawingsaid sheet metal in-V wardly to release said door from the opening, anda member for operating both said means.

3. In a structure of the class described, a receptacle having a sheetmetal lining terminat-ing in a tubular opening,.a support` for saidopening, a door adapted to movef'into -grooved portions therein adaptedto be flexed to pei-mit the door to expand and contract Y withoutstretching thesheet niet-al facing.

5. In combination, a .door having a sheet metal periphery, a dooropening having a sheet metal lining, backing for said lining, means forexpanding said periphery outwardly into contact with said lining, andmeans for positively withdrawing said periphery'- inwardly. l

6. In combination, a door having a sheet metal periphery, a door openinghaving a Vsheet metal lining, backing for said lining, means forexpanding said periphery out-4 wardly. into contact with said lining,and cainmeans for positively withdrawing said periphery inwardly.

7. In combinatioma door having a sheet metal periphery, a door openinghaving af' sheet metal lining, backing forY said lining, aV pluralityvof members extending radially outwardly into contact with the sheetmetal of said periphery, and cam-operated means for positively forcingsaid members outwardrly or inwardly to cause saidperiphery'to expand orcontract.

. 3,.v In combination, a door having a sheet metal periphery, `a dooropening having a sheet metal lining, backing for said lining, aplurality of members extending radially outwardly into contact with thesheet metal of said periphery, means for securing said periphery toVsaid members, and cam-operated means for `positively forcing saidmembers outwardlyor inwardly to cause said periphery to expand oi'contract.

` 9. In fcombiiiation, a door havinga sheet metal periphery, a dooiopening'having a sheet metal lining, backing for said lining, means forexpanding said periphery outmeans for positively Vwithdrawing saidperiphery inwardly, the sheet metal Vof the door covering havi'ngridgeslformed therein toi'- 11. In combination, an oven having a lateralopening, a door movable into said opening, andan inwardly `extending rimsurrounding said door andserving to hold liquid rounding said door andserving tohold liq-V uid leaking arounds'aid cover, said ,opening andthe periphery of said door being correspondingly tapered. f

13. In combination, an oven having a lateral opening, a door movableinto said openlng, and an inwardly extendmg rim surrounding said doorand serving to hold liquid leaking'around said cover, said opening andthe periphery of said door beingwcorrespondingly tapered, and the vrimsubstantially touching said periphery when the Ydoor is closed. v n v Intestimony whereof, I have hereunto set my hand this 17th day ofSeptember, 1928.

ROSCOE S. I-IEISE.l

